Fix hx-live form reset state (#3933)

Fix hx-live form reset state

Author: scriptogre

src/ext/hx-live.js

@@ -134,7 +134,11 @@
                     : (value ? 'true' : 'false');
                 e.setAttribute(name, attrVal);
             } else if (isPropAttr) {
-                if (value === false || value == null) {
+                if (name === 'checked' || name === 'selected') {
+                    let present = !!value;
+                    e[name] = present;
+                    e.toggleAttribute(name, present);
+                } else if (value === false || value == null) {
                     e[name] = (typeof e[name] === 'boolean') ? false : '';
                     e.removeAttribute(name);
                 } else if (value === true) {

test/tests/ext/hx-live.js

@@ -1927,6 +1927,19 @@ describe('hx-live extension', function () {
         mirror.hasAttribute('checked').should.equal(true);
     });
 
+    it('keeps checked and selected false after form reset when the result is zero', function() {
+        playground().innerHTML = `
+            <form>
+                <input type="checkbox" :checked="0">
+                <select multiple><option :selected="0">One</option></select>
+            </form>
+        `;
+        htmx.process(playground());
+        playground().querySelector('form').reset();
+        playground().querySelector('input').checked.should.equal(false);
+        playground().querySelector('option').selected.should.equal(false);
+    });
+
     it(':value syncs property and attribute', async function() {
         playground().innerHTML = `
             <input id="src" value="hello">